1. Field of the Invention
The present invention relates to a data storage tape cartridge having a housing within which a transponder is secured for identification of the cartridge.
2. Background Art
Tape cartridges provide a practical and economical mechanism for long-term data storage. Tape cartridges have one or two reels on which a data storage tape is wound. Data storage tapes are comprised of a flexible web on which a coating is applied that records information caused by changes in magnetic fields, exposure to light, and the like. A data storage tape cartridge is inserted into a tape drive to allow data to be written to, or read from, the data tape.
Single hub cartridges are accessed by a tape drive as the tape is withdrawn from the cartridge and pulled along a tape path across at least one read/write head. After the tape is accessed, it may then be rewound onto the cartridge and returned to storage. Tape cassettes are cartridges that generally include two hubs. Tape is wound between the two hubs and pulled across a read/write tape head.
Data storage tape cartridges must be identified in some way so that the contents of the tape can be identified. One type of information about tape cartridges that may be used for identification is information relating to the type of data stored on the tape. Such information can include a list of files stored on the tape, the time and date of data storage, expiration dates, file ownership information, and the like. Another type of information that may be used for identification regarding each tape cartridge includes information about the cartridge itself such as the serial number of the tape, type of cartridge, type of tape, cartridge manufacturer information, and the like. Another type of information about a cartridge may be tape cartridge history information. An example of tape cartridge history information may include the number of times the cartridge has been loaded onto a tape deck, the number of cartridge read/write operations, the age of the cartridge, access error data, and the like.
Cartridge identification information may be simply provided as a visually readable label, a bar code tag, a radio frequency tag, or a transponder. Visually readable tags are not well suited for large automated tape libraries. Bar code labels are not rewriteable and can only provide a limited amount of information. A radio frequency tag or transponder may include a dynamic memory that may be accessed by a radio frequency read/write unit when the transponder tag is placed in close proximity to the reader. Transponders may include substantial memory that can be either permanent or read/write memory depending upon the type of information to be stored on the transponder tag. Examples of radio frequency tags and radio frequency readers for use in tape cartridges are disclosed in U.S. Pat. Nos. 5,971,281; 6,081,857; 6,226,688; and 6,466,990.
One disadvantage of radio frequency identification (RFID) tags is that they are normally permanently affixed within the tape cartridge. A RFID tag that is assembled to the inside of a tape cartridge cannot be easily upgraded. If the RFID tag is located inside the cartridge, it must be inserted during assembly of the cartridge and cannot be accessed without disassembly of the cartridge. With this type of RFID tag system, it is not possible to change the write protected data on the RFID chip. Mounting the RFID chip inside the housing of a tape storage cartridge reduces design flexibility. In addition, if the RFID tag becomes inoperative for any reason, it is necessary to disassemble the tape cartridge to replace the RFID chip.
One example of a tape storage cartridge having a RFID tag is disclosed in U.S. Pat. No. 6,304,416. This patent discloses the concept of providing a RFID tag that is mounted at a 45° angle relative to two sides of a data tape storage cartridge. The data storage tape cartridge disclosed in this patent requires assembly of the RFID tag chip when the tape storage cartridge is initially assembled. The 45° orientation of the RFID tag permits the RFID tag to be accessed through one of two different walls of the data storage tape cartridge. While this design provides a dynamic RFID tag system that may be accessed to update the RFID tag memory with additional files, fields, or other data, if the RFID tag becomes inoperable it is necessary to disassemble the tape cartridge to obtain access to the RFID tag.
Tape cartridges may include a write protect switch that may be used to either inhibit or permit data to be written to the data storage tape. If the write protect switch is in the locked position, it is not possible to write to or erase the data storage tape. If the write protect switch is in the unlocked position, the tape may be freely accessed and read/write operations may be performed on the data storage tape. Write protect switches are normally secured to the tape storage cartridge and are assembled to the cartridge when the cartridge is initially assembled. If the write protect switch is non-functional or becomes broken in the course of normal use, the cartridge must be disassembled or replaced by another cartridge. Applicants' assignee developed a RedWood model storage cartridge that included a write protect switch on a removable portion of the data storage cartridge. While this design permitted separate assembly and replacement of the write protect switch, it did not disclose or suggest the concept of providing a transponder or RFID tag for the tape storage cartridge. The mechanical ID used with the RedWood system was a mechanical ID tag that was limited to identification of the tape cassette by a gap/no gap pin spring system. The RedWood data storage tape cartridges also could include bar codes and human readable labels depending upon a customer's requirements.
These and other problems and disadvantages of the prior art data storage tape cartridge ID systems is addressed by Applicants' invention as summarized below.